The use of antidepressants in bipolar illness remains controversial. This controversy continues to be fuelled by short-term studies that inconsistently report efficacy or no benefit. However, long-term studies have been consistently unfavourable, suggesting that understanding the long-term course of the illness in the setting of antidepressant treatment is important. This is an extraordinary case in which prospectively collected daily mood ratings were available in a type I bipolar individual who had experienced minimal medication changes over a 21-year period was reviewed. Data regarding the number of euthymic days in the setting of antidepressant use and after antidepressant discontinuation were collected.
Induction of cycling and increase in the number of depressed days occurred after five years of continuous serotonergic antidepressant administration. Discontinuation of antidepressants after 11 years of continuous use was associated with only a partial improvement which had a delayed onset. Cycling and increase in depression was noted after years of continuous use of serotonergic antidepressant treatment. Antidepressant-associated destabilisation may occur after long-term exposure and may be associated with prolonged worsening even after antidepressant discontinuation.